Well-known member

I've successfully completed 2 SLAMs, brought my CYA to what I feel confident is 40, but I'm still losing FC at what I would consider a fairly rapid rate. My pool only gets full sun about 6-8 hrs a day (mid morning through 3 pm) so it is shaded in the heat of the day and we aren't even close to the heat of our summer. I am having to add a shade under 3 quarts of 10% daily. I have my wife, who is off on maternity leave, add 1 quart around lunch not aiming for a specific number, just ensuring I don't drop below the minimum. I'll add another around 4, and then another after dark to get the FC between 8 and 9 for the night. Any suggestions or thoughts? It's getting expensive and I won't have anyone home to put an insurance quart of chlorine in much longer.

Well-known member

Adding 6 ppm, and I just successfully completed my second OCLT just 3 days ago so I'm certain that algae isn't my problem. The SLAM I completed was merely a week before that, so I'm not gonna do a SLAM on a weekly basis, that's not feasible or even sensible. Is 4-6 ppm accurate for a cya of 40? I know I haven't dropped below my minimum because I'm having the midday addition of chlorine to maintain it on the high end of my recommended FC range. I'm gonna add more stabilizer tomorrow to reach a cya of 50 and see if that helps. If not I may have to go with tablets unless someone has another suggestion, because I won't have the means to maintain my levels during the day nor do I want to buy 6 gallons of chlorine every week.

Well-known member

Yes I know the range is 3-7 and that is what I'm saying. I am having to overshoot the max and add a quart midday in order to keep it from dipping down below the minimum. If I bring it to 9 ppm FC at night, add 6 ppm per day to maintain that level, then just stopping at the target of 5-7 would cause me to dip below the minimum. The biggest problem is, I'm not going to have someone there everyday to add chlorine midday.

Quick Google - Ramer is in Alabama? Per PoolMath, 3 qts of 10% in a 21,000 gal pool only raises FC by 3.6, not 6ppm. So you are on the upper end in the daily chlorine usage that pooldv suggested and not really surprising, bet your weather is similar to mine in Houston and I'm using about 3-3.5 ppm per day with a bit more sun exposure than yours, but I keep my CYA up at 50-60. You can try raising CYA see if that helps.

Regarding the 'feeding' you can raise FC at night - put all 3 quarts in - and let it drop through the day. Might use a little more chlorine but it saves you having to be there every lunchtime. No other way around it, unless you get some kind of automated feeder system (like a Stenner) or a SWG.

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